More on Brain Health

You can't remember the route to a restaurant you've been to many times before or the birthday present a friend gave you a month ago.

Then comes the worry.

Is your forgetfulness a sign of something serious, like Alzheimer's disease or another form of dementia? Such brain freezes happen to most of us, to different degrees, as we age.﻿ Even experienced public speakers have their "Oops" moments, when a word or term they use on a daily basis simply refuses to come to mind.

But while such common memory lapses are frustrating, they don't necessarily mean Alzheimer's is at the door. If your lapses aren't disrupting your life, there's no need to be actively worried, experts say.

"The key issue is whether cognitive changes are significantly interfering with daily activities, " says Kirk R. Daffner, M.D., chief of the division of cognitive and behavioral neurology at Boston's Brigham and Women's Hospital. If that's happening, you should consult your doctor. Your lapses may well have very treatable causes. Severe stress, depression, a vitamin B12 deficiency, insufficient sleep, some prescription drugs and infections can all play a role.

Even if these factors don't apply to you, your memory isn't completely at the mercy of time. Studies have shown that people who exercise, stay mentally active, socialize regularly and eat a healthy diet can minimize memory loss.

Still worried? See below for six types of normal memory lapses that are not signs of dementia — plus tips on how to counter them.

1. Absentmindedness

Where in the world did you leave your keys? Or why the heck did you walk into the living room anyway? Both of these very common lapses usually stem from lack of attention or focus. It's perfectly normal to forget directions to somewhere you haven't visited in a while. But "if you've lived on a block for 10 years, and you walk out the door and get lost, that's much more serious," says Debra Babcock, M.D., of the National Institute of Neurological Disorders and Stroke.

Memory tip: Focus on what you're doing or thinking in any given moment, and you'll head off a lot of these lapses. If you find yourself in the middle of one, retracing your steps, mentally or actually, can help.

2. Blocking

This is the frustrating tip-of-the-tongue moment. You know the word you're trying to say, but you can't quite retrieve it from memory. It usually happens when several similar memories interfere with each other. A 2011 study, published in the journal Brain Research, showed that elderly participants had to activate more areas of the brain to perform a memory task than the study's young subjects. "We're all accessing the same brain networks to remember things, says Babcock, "but we have to call in the troops to do the work when we get older, while we only have to call in a few soldiers when you're younger."

Memory tip: Review mentally — or even write down — the elements or facts of a story or event before you talk about them. If you find yourself stuck in the moment, try to remember other details about the event, name or place, which often will trigger the memory you are searching for.

3. Scrambling

This is when you accurately remember most of an event or other chunk of information, but confuse certain key details. One example: A good friend tells you over dinner at a restaurant that she is taking out a second mortgage on her home. Later, you correctly recall the gist of her news but think she told you during a phone conversation.

Research points to the importance of the hippocampus — a region of the brain crucial in the formation of memories about events, including the particular time and place they occurred. Scientists estimate that, after the age of about 25, the hippocampus loses 5 percent of its nerve cells with each passing decade.

Memory tip: Draw on mental cues from an experience or event to trigger an accurate recollection. Focus on piecing together specific details of the memory — the time, the place, the people you saw, the reason for the event, topics of conversation.

4. Fade Out

The brain is always sweeping out older memories to make room for new ones. The more time that passes between an experience and when you want to recall it, the more likely you are to have forgotten much of it. So while it is typically fairly easy to remember what you did over the past several hours, recalling the same events and activities a month, or a year, later is considerably more difficult. This basic "use-it-or-lose-it" feature of memory known as transience is normal at all ages, not just among older adults.

Memory tip: Studies show that events we discuss, ponder over, record or rehearse are recalled in the most detail and for longest periods of time. So one of the best ways to remember events and experiences — whether everyday or life changing — is to talk or think about them.